Can you prove they are? I think “AIs are conscious” is an extraordinary claim requiring extraordinary evidence. The burden is on the claimant to provide evidence it is conscious, and I suspect any evidence you can provide has alternative explanations. The majority of claims I’ve seen like this amount to “how do you know humans are conscious in a way that’s distinct from a next token predictor.” I do not find those claims compelling.
If object a behaves like it has property x and you cannot otherwise test out x, then it is logical to assume it indeed has x. In this instance, 'object a has property x' is not an extraordinary claim at all. It is simply pointing out what has been observed. In fact, what is an extraordinary claim is saying what looks like a duck, quacks like a duck and moves like a duck is not a duck.